摘要:

Some species ofLiliaceaecollected in N Cyrenaica are examined from the karyological point of view. They are:Allium negrianumMaire & Weiller(2n = 2x=16),Allium ascalonicumL.(2n = 2x= 16 + 1B),Allium erdeliiZucc.(2n = 2x=16),Allium longflnumPamp.(2n = 4x= 28),Allium roseumsupbs.tourneuxii(Boiss). Bartolo et al. stat. nov.(2n = 2x=16),Allium ruhmerianumAscherson ex Durand & Barratte(2n = 3x= 33),Allium orientaleBoiss.(2n = 2x= 16), Scilla africanaBorzì& Mattei(2n = 2x= 14),Scilla barbacaprae(Ascherson & Barbey ex Durand & Barratte) Brullo & Furnari(2n = 2x—14),Scilla cyrenaica(Pamp.) Bartolo et al stat. nov. (2n= 2x= 14),Scilla fallaxSteinh. (2n = 2x= 11),Urgfnea undulata(Desf.) Steinh. (2n= 2x = 20),Urginea maritima(L.) Baker(2n = 2x= 20), Ornithogfllum libyeum (Béguinot & Vacc.) Béguinot & Vacc.(2n = 2x=14),Bellevalia sessiliflora(Viv.) Kunth(2n= 2x= 8),Bellevalia cyrenaicaMaire & Weiller(2n = 2x= 8). Besides a new section ofAlliumis described and namedRhyncbocaipumBrullo sect, nov., which is typified byA. ruhmerianum.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670329

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This research has its own main propose to describeBetula aetnensiswood comparing it toBetula pendulaone. The most significant anatomic character found inBetula aetnensis, even if at a low rate, regards vessels with simple perforation and at the same time, others with scalariform perforation. In comparison withBetula pendula, the decrease in the number of bars is remarkable in scalariform perforation.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670330

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The «VicieaeDatabase Project» is an experiment in taxonomic methods with two purposes: to build and operate a monographic computer database for the tribeVicieae (Legnminosae): and to provide novel taxonomic services from an information centre using the computer database, project personnel and a collection of materials. In the first phase the database has been constructed with files containing nomencla- tural data, morphological descriptions, geographical distributions and chemo-taxonomic records in varying degrees of completeness for species in the tribe. In the second phase an international study group of scientists specialising in theVicieaehas been evaluating some of the novel services. Present experiments are with: 1) a pamphlet series, 2) a data enquiry service), 3) a tailor-made product service, 4) a materials supply service, and 5) makingVicieaedatabase contributions to other database projects.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670331

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The chromosome number 2n= 22 is recorded forL. intermediaWebb ssp.intermedia, L. intermediassp.spathulata(J.A. Schmidt) B. Petters (new record),L. libyca(Viv.) Meisn.,L. marginata(Webb) Christ, andL. palmensisWebb (new record);2n= 24 forL. maritima(L.) Desv.; and 2n= 42 forL. arabica(Boiss.) Muschler (new record). Deviating numbers are observed in single root tips and PMC's:n= 22 and 2n= 44 inL. palmensis; n=11, 24, 35 and 2n= 30, 36, 42, 48 inL. maritima;andn= 24, 27 and2n =ca. 96 inL. arabica.The annuals,L. arabicaandL. libyca, are found to be predominantly self-compatible and autogamous; the perennials more or less self-incompatible and normally outcrossing. The endemic Macaronesian species,L. intermedia, L. marginata, andL. palmensis, are almost completely interfertile. Internal isolation barriers exist betweenL. arabica, L. libyca, andL. maritima, and between these species and the Macaronesian ones.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670332

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Le genreCarlinaL. en Sardaigne est répresenté parCarlina macrocephalaMoris, endémique des hautes montagnes du centre-Sardaigne, de la Corse et des Apennins Toscans,C. corymbosaL. s.l. etC. lanataL., deux espèces sténo-méditerranéennes et par C. racemosa L., repandue dans le bassin occidentale de la Méditerranée. De chaque espèce on a donné quelques remarques de charactère systématique, biologique, écologique et son aire de répartition dans l'île.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670333

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The pollen grains ofQuercus cocciferas.l. are characterized by a lined exine made up to long flat plicae with abundant perforations of the tectum (SMIT, 1973) and a long colpus with a membrane, rugulate edges and evident porus (MARIANI COLOMBO, CHIESURA LORENZONI, GRIGOLETTO, 1983).

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670334

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670335

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Une analyse de la distribution d'environ 500 nombres chromosomiques (littérature et nos résultats), montre l'ampleur de la variation au sein du genre(2n= 6 à2n =108) avec x = 6 et 9 comme nombres de base les plus fréquents. Des investigations caryologiques portant sur 18 taxons, dont 6 nouvellement étudiés, ont été faites aux niveaux taxon, population, individu et organe. La variation chromosomique, d'absente chez. O.wiedemanniiBoiss., atteint son maximum chez O.divergensBoreau (2n= 11 à2n= 108), espèce qui comporte de nombreux individus mosaïques avec une importante stérilité mâle. La multiplication végétative favorise la prolifération des divers cytotypes. Aux causes classiques de la variation (allo- et autopolyploïdie, etc) s'ajoute l'existence de liaisons interchromosomiques. Les niveaux évolutifs des taxons étudiés sont précisés par l'examen des caractéristiques caryologiques qui révèle l'existence de deux amphi- ploïdes probables (O. creticumZahar. et O.brachystylumZahar.). Il est établi l'interfécondité de plusieurs espèces éloignées par exemple O.atticumBoiss & Heldr. et O.narhonenseL. L'étude des possibilités d'hybridations naturelles et celle de la variation chromosomique intra- et interindividuelle apparaissent essentielles pour une approche explicative de la systématique et des phénomènes de microévolution de ce genre.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670336

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The background to the establishment of a European Taxonomic, Floristic and Biosystematic Documentation System (EDS) for the vascular plants of Europe is discussed and the Viewdata system used by the EDS is explained in terms of its advantages to both taxonomic and non-taxonomic users. The availability and possible future expansion of the database are outlined.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670337

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The validity and the taxonomic status ofRacomitrium marginatumLojac. are discussed. This doubtful Sicilian moss, validly reported in the «Index muscorum», is closely related toR. lanugfnosum(Hedw.) Brid. of which it has been considered as a mere synonym. Studying a specimen ofR. lanugfnosumfrom vicinity of the locus classicus ofR. marginatum, BRIZI remarks the insubstantiality of this species and affirms that it is a form ofR. lanugfnosumadapted to arid and dry environments. According to this opinion and on the basis of the examination of the specimen studied by Lojacono (PAL), it has been given a more suitable interpretation of this doubtful entity. Therefore it is described as a new form namedRacomitrium lanugfnosum(Hedw.) Brid fo.aetnenseDia et Raimondo.

ISSN:0083-7792    

DOI:10.1080/00837792.1984.10670338

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor